In various industries, chemical delivery systems are used to supply chemicals to processing tools. Illustrative industries include the semiconductor, pharmaceutical, biomedical, food processing, household product, personal care product, or petroleum industries.
The chemicals being delivered by a given chemical delivery system depend, of course, on the particular processes being performed. Accordingly, the particular chemicals supplied to a semiconductor processing tool depend upon the processes being performed inside the tool. Illustrative semiconductor processes include etching, cleaning, chemical mechanical polishing (CMP), and wet deposition (e.g., spin-on, copper electroless, electroplating, etc.).
Commonly, two or more fluids are combined to form the desired mixture for the particular process. The mixtures may be prepared in batches, on- or off-site, and then shipped to the processing location. Alternatively, the mixtures may be prepared at the point-of-use using a suitable blender system.
U.S. Pat. No. 6,050,283 to Air Liquide America Corp. discloses a system and method for mixing and/or diluting ultrapure fluids, such as liquid acids, for semiconductor processing.
U.S. Pat. No. 6,799,883 to Air Liquide America L.P discloses a method and apparatus for continuously blending a chemical solution for use in semiconductor processing.
U.S. Pat. No. 6,923,568 to Celerity, Inc. discloses a method and apparatus for blending and supplying process materials, particularly ultra-high purity chemicals.
U.S. Pat. No. 7,344,297 to Air Liquide Electronics U.S., LP, discloses a method and apparatus for asynchronous blending and supply of chemical solutions.
A need remains for methods and systems for high precision, continuous blending of solutions.